The Cephalopod's power draw claims 146mA on the -12 rail, which is close enough to that, assuming the entirety of that rail is going into the heater. While it's possible that Sognage were extra-clever with their design and devised some sort of startup current limiter, industry trends of putting tubes in things like synths and guitar pedals suggest that they may be current-starved as Luchog fears. I can't find anything to suggest either way on this, so without the developer's input or someone willing to open up their module and draw out the schematic, we can only really speculate.

The main issue that I noted was that Sognage state quite clearly on the Cephalopod page is used for their instrument preamp input; which means it isn't being used for an filtering or tone-shaping after that point. And even if it was, it's a pretty crap tube for that purpose.

I believe what Luchog was trying to say though is that if OP is looking to add some tube modules by means of ones that only use the tube as a signal preamp or booster, they might be better off just buying one module like an L1 Tube VCA or GMSN! Safety Valve (or both!) and plugging other modules into that as needed.
That would be my 2¢, at least.

Or just use a regular solid-state preamp, since there's very little reason to use such a basic tube preamp in Euro; waste of power and money and hp. If you're going to spend the premium that most manufacturers charge for tube-based circuitry (and fully justified, given the the efforts involved in designing and building such quirky devices); then at least get your money's (and hp's) worth by using circuits that have an actual, not-too-subtle-to-notice effect on the sound. As opposed to falling for the same trend-following overpriced hype so popular in audiophile circles.

my use of tubes from 2 days ago. had to reconstruct the settings on the E370 as good as possible (headphone mix)

E370 VCO thru tubes, then thru NG

first no tube / at sec 7 switch to tube
at sec 15 i close NG to intended state and back to no tube ( set by crossfader) / at sec 22 back to tube sound

could be that you get samish results with some no-Tube overdrive modules.
i don´t do any claims in that direction.
(the patch worked better in its original settings /i deajusted the settings on the E370 in the meantime)

OP, if you ever do get some more power in your system, I’d highly suggest you take a look at the RK4. It’s a filter topology unique to the Eurorack world, and therefore sounds and behaves like nothing else. Easy to tame, and easy to make nasty.
Anyways, hope ya ou find what you’re looking for.

OP, if you ever do get some more power in your system, I’d highly suggest you take a look at the RK4. It’s a filter topology unique to the Eurorack world, and therefore sounds and behaves like nothing else. Easy to tame, and easy to make nasty.
Anyways, hope ya ou find what you’re looking for.

do you have a suggestion on how to get more power?(apart from the obvious RPK which is overkill maybe for 1 modules power)

this thread has made me get a strong ear out for RK3 and RK4, but 1 amp each is no joke. My 7u has Malekko Power, at 2a its typically more than enough but i cant see how to even add one metasonix module without gutting the whole power system. i want to believe somehow its feasible to just squeeze one in but it realistically it seems you have to plan a system for it.

This is an area that requires a bit of knowledge and research to know what you are getting. If a tube has low power consumption it is very likely a “starved plate” design. These are generally based on diy guitar pedal designs like the valvecaster. They do impart distortion and color and there is nothing wrong with them if you like what they do. Low power tube designs are legitimate but different designs and characteristics than tubes running at proper power.

In the eurorack setting a starved tube design is much simpler than a design that boosts voltage and consumes lots of amperage.

When you see tube filters in eurorack there are different types:

1- There are normal solid state filters with a valvecaster design tacked on: these are gimmicky imho as the tube isn’t integral to the filter and you would be better off just getting a starved plate tube vca/distortion and combining it with any filter you want.

2- There are a couple filters that are a hybrid of a normal eurorack design that actually incorporates the tube into the filter circuitry such as a Vacumform multi mode that incorporates tubes into the filter stages.

3- Then you have unique circuits like metasonix where tubes are exploited to do strange and unique filtering (among other things) at the economy of minimal tubes. These don’t exactly behave like a typical filter but that’s the charm.

This is an area that requires a bit of knowledge and research to know what you are getting. If a tube has low power consumption it is very likely a “starved plate” design. These are generally based on diy guitar pedal designs like the valvecaster. They do impart distortion and color and there is nothing wrong with them if you like what they do. Low power tube designs are legitimate but different designs and characteristics than tubes running at proper power.

In the eurorack setting a starved tube design is much simpler than a design that boosts voltage and consumes lots of amperage.

When you see tube filters in eurorack there are different types:

1- There are normal solid state filters with a valvecaster design tacked on: these are gimmicky imho as the tube isn’t integral to the filter and you would be better off just getting a starved plate tube vca/distortion and combining it with any filter you want.

2- There are a couple filters that are a hybrid of a normal eurorack design that actually incorporates the tube into the filter circuitry such as a Vacumform multi mode that incorporates tubes into the filter stages.

3- Then you have unique circuits like metasonix where tubes are exploited to do strange and unique filtering (among other things) at the economy of minimal tubes. These don’t exactly behave like a typical filter but that’s the charm.

What do you know, there's more than one way to use tubes in a module, who would have thought.

do you have a suggestion on how to get more power?(apart from the obvious RPK which is overkill maybe for 1 modules power)

this thread has made me get a strong ear out for RK3 and RK4, but 1 amp each is no joke. My 7u has Malekko Power, at 2a its typically more than enough but i cant see how to even add one metasonix module without gutting the whole power system. i want to believe somehow its feasible to just squeeze one in but it realistically it seems you have to plan a system for it.

Eh, wish I had a better answer for you; I use two Doepfer PSU3s and a PSU2.
I know nothing about Malekko’s power supplies or the current load in your system. You might be able to squeeze one or even two in, depending on how much current you’re drawing now, and how well it handles itself close to its current limit.
If you’re looking for more power, Trogotronic’s M15 DIY power supply is probably the cheapest way to do it, short of buying some MeanWell supplies off of Mouser and hacking something together something that way.
I saw some “soft-start” ribbon cable attachments a while ago that are meant to slowly bring a module up to power without any inrush current, but I have no experience with them.

do you have a suggestion on how to get more power?(apart from the obvious RPK which is overkill maybe for 1 modules power)

this thread has made me get a strong ear out for RK3 and RK4, but 1 amp each is no joke. My 7u has Malekko Power, at 2a its typically more than enough but i cant see how to even add one metasonix module without gutting the whole power system. i want to believe somehow its feasible to just squeeze one in but it realistically it seems you have to plan a system for it.

Eh, wish I had a better answer for you; I use two Doepfer PSU3s and a PSU2.
I know nothing about Malekko’s power supplies or the current load in your system. You might be able to squeeze one or even two in, depending on how much current you’re drawing now, and how well it handles itself close to its current limit.
If you’re looking for more power, Trogotronic’s M15 DIY power supply is probably the cheapest way to do it, short of buying some MeanWell supplies off of Mouser and hacking something together something that way.
I saw some “soft-start” ribbon cable attachments a while ago that are meant to slowly bring a module up to power without any inrush current, but I have no experience with them.

thank you, both forthe suggestions
this is exactly what i needed to hear. ive got a couple soft starts already, theyre amazing! they should be integrated onto busboards themselves. was curious if the tubes needed longer to warm up. im glad to hear it works well with metasonix because i think that will allow me to cram an RK3 into my system, which sits around 1.2 amps so the 1 amp startup would be an issue

this thread has made me get a strong ear out for RK3 and RK4, but 1 amp each is no joke. My 7u has Malekko Power, at 2a its typically more than enough but i cant see how to even add one metasonix module without gutting the whole power system

Power 1.3 bus? That should be enough to run a couple of our RK modules.

this thread has made me get a strong ear out for RK3 and RK4, but 1 amp each is no joke. My 7u has Malekko Power, at 2a its typically more than enough but i cant see how to even add one metasonix module without gutting the whole power system

Power 1.3 bus? That should be enough to run a couple of our RK modules.

thanks! i should have specified up front that its a 7u full of other modules sitting around 1.2 amps on the positive rail, so the 1 amp on cold start would (i assume) put it over.

too late anyway, i already ordered it today to catch a sale just hoping itll work with the soft-start, otherwise ill figure it out

Tubes definitely need time to warm up and stabilize; but it only takes a few minutes (5-10 depending on the module), so as long as you're not trying to jam the moment you flick the thing on, you're good.